Printing press



P 23, 1947- w. w. DAVIDSON 2,427,904

PRINTING PRESS Original Filed May 9, 1939 9 Sheets-Sheet 1 llu Hlllll 47 j flqavzor v 9 7 4/40/12 7//d gamafsarz/ W. W. DAVIDSON Sept. 23, 1947.

PRINTING PRESS Original Filed May 9, 1939 9 Sheets-Sheet 2 2/2 213 Limwl 2v 16K lei zfl 2101' Ira/0712507 mm Wardfiawzd on p 1947' w. w. DAVIDSON 7 2,427,904

PRINTING PRESS Original Filed May 9, 1939 9 Sheets-Sheet 4 mm Dal/ids 0n Sept. 23, 1947.

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PRINTING PRESS Original Filed'May 9, I939 9 Sheets-Sheet 6 ZZ :LUQ 77150 7 Zw'a/n, Wardjauxkoiz Sept. 23, 1947. i -w. w. DAVIDSON 2,427,904

7 PRINTING PRESS Original Filed May 9, 1939 9 Sheets-Sheet 7 EUZRZOT Wm 7/074 fizz/1623077,

p 3, 1947. w. w; DAVlDSOh L 2,427,904

PRINTING PRESS Original Filed May 9, 1939 9 Sheets-Sheet 8 p 1947- V w. w. DAVIDSON 2,427,904

PRINTING PRESS Original File d May 9, 1939 9 Sheets-Sheet 9 Patented Sept. 23, 1947 PRINTING PRESS William Ward Davidson, Evanston, Ill., assignor to Davidson Manufacturing Corporation, a corporation of Illinois Original application May 5, 1939, Serial No.

272,053. Divided and this application December 7, 1942, Serial No. 468,099

Claims.

The present invention relates to new and useful features in the construction and general assembly of rotary printing presses and to certain new and useful improvements Which have a broader application to presses generally.

The present application is a division of application Serial No. 272,653 filed May 5, 1939, which application has matured into Davidson Patent No. 2,306,044, issued December 22, 1942. There are also other applications which have been copending with said application Serial No. 272,053, in which some of the divisible features disclosed in said application will be patented.

It is one of the objects of the invention to provide a printing press which can be used in general business offices whose employees are not skilled in the art of printing, yet satisfies the requirements of printers generally and can be used in printing plants for light and fast work.

In providing such a press, the question of price range is of prime importance. Many of the improvements developed in recent years amount to nothing more than accessories added to otherwise old presses and the cost of a particular installation was indexed by how many additional accessories were required by a purchaser. No substantial reorganization of the press assemblies has been had to eliminate parts and elements conventionally believed necessary. In fact, many manufacturers of presses prefer to have one basic unit to which accessory units can be added. This reduces the manufacturers inventory overhead and shoulders upon the purchaser the cost-burden of the aggregately assembled units that are necessary to provide the results the purchaser asks for.

It is one of the purposes of the present invention to provide a reorganized press construction which accomplishes the results of the larger and more complicated conventional presses and which can be furnished at a single price within that which general business ofllces would be willing to pay to have an installation made to take care of their light work.

In providing a press that can be operated successfully by employees in general business ofices it is important that the press be fool-proof for unskilled labor. Simplicity and ruggedness make it possible to accomplish this, and in the present invention these features have been emphasized. On the other hand these features make the present press desirable for use in printing shops and although the press of the present invention is already a high speed press within the meaning of these words in the art, its low cost enables work speeds to be multiplied in relation to equipment overhead since two or more of the present presses may be installed within a budget normally allocated for a single con- 2 ventional press. This enables a multiplication of work to be turned out on the same overhead.

Not only this, but the press of the present invention performs work acceptable to printers and the discriminating public alike, Within the standards and criterion that have come to be expected of a printing process. In the present invention the process is preferably lithographic although the press illustrated is designed, with little change, to operate as a direct or type printing press, within the purposes and objects of the invention.

In addition to these features, I provide an improved rotary press having only two cylinders in the printing couple, and to the end that the operator may manage the press with a minimum amount of movement around the press, all the controls are readily reached from the feed station; the dampening and inking assemblies are located on top where their condition and the functioning of the fountains and rollers can be seen at a glance. This construction provides adequate room at the back of the press to replace the lithographic plate without changing the settings or position of associated parts when it is necessary to give to the cylinder the atten tion needed in setting up and adjusting it to run off a printing job.

In the present construction, once the ink impression is applied to the paper or other work material, the printed surface is seldom touched, yet in the preferred form of the invention the sheet is delivered right side up whether it is printed on the underface (as in offset printing) or on the upper face (as in direct printing) The broad concept of the two purpose press is one of the features covered in the parent application Serial No. 272,053. The broad concept of delivering either side up, especially from a twopurpose press and a preferred means for accomplishing this are covered in a copending application, Serial No. 324,627, filed March 18, 1940, which has matured to Patent No. 2,374,688. The present divisional application is intended to cover another means of accomplishing this result according to which a deflector is used when it is desired to turn the sheet over after offset printing. When the deflector is used, there is the additional advantage that the sheet is delivered to the same side of the press from which it was fed. The operator can see it without moving from his station.

I provide an improved form roller throwout which can be operated selectively to throw out either one or both of the form rollers, namely, the dampening and the inking form rollers. Moreover, the rollers are mounted in an improved manner whereby the shafts can be withdrawn to remove them without disturbing their adjustment.

Moreover, I recognize and capitalize upon the fact that with the main cylinder making more than half a revolution between inking contacts with the form rollers, I can eliminate many distributor and form rollers heretofore believed necessary. The off-contact time makes it possible with the size and form of the rollers employed in the present invention to pick up and adequately distribute the ink before repeated inking contacts with the plate.

These being among the objects of the present invention, other and further objects will become apparent from the drawings herein, the description relating thereto and the appended claims.

Referring now to the drawings:

Fig. 1 is a side elevation of a preferred form taken inside the frame member on the left hand side from the feed station and looking toward the right hand frame member with those parts shown in section that engage the left hand frame member;

Fig. 2 is a section through the middle of the press on a plane normal to the cylinder and rollers;

Fig. 3 is a section taken on the line 3-3 in Fig. 2;

Fig. 4 is a perspective view of the isolated drive mechanism for the several parts that are positively driven in the invention;

Fig. 5 is a perspective view of the isolated cam drive for the sheet skip control;

Fig. 6 is a close up of the feeder mechanism shown in Fig. 2;

Fig. '7 is a section taken upon the line 'l'l in Fig.

Fig. 8 is a top plan of the inking and dampening mechanism with certain parts in partial section;

Fig. 9 is a restricted section taken longitudinally through the cylinders when they are in separated position;

Fig. 10 is a scaled view of the cam and follower mechanism for the separator roller;

Fig. 11 is a scaled view of the cam and follower mechanism for the lower feed roller;

Fig. 12 is a perspective of the mechanism shown in Fig. 11;

Fig. 13 is a caled view of the cam and follower mechanism for the upper feed roller;

Fig. 14 is a perspective view of the mechanism shown in Fig. 13;

Fig. 15 is a view similar to Fig. 1 showing an adaptation of the preferred form for direct or type printing;

Fig. 16 shows the clean-up attachment, partly in section, for the ink assembly.

Before referring to the drawings in further detail, a better understanding of the drawings and the description to follow will be had if, at thi time, the cycle of operation of the embodiment illustrated is briefly outlined as it would appear to one standing beside the physical machine observing it in operation.

GENERAL ORGANIZATION The main cylinder 20 is mounted to rotate in the direction indicated by the arrow 26 away from the feed side of the press which in the view shown in Fig. 1 is the right side. A plate segment 2! and a platen segment 22 are mounted on the cylinder with a cam segment 23 located between the trailing edge 24 of the plate and the leading edge 25 of the platen segment.

The blanket cylinder is mounted below the main cylinder upon a shaft 3| that is eccentrically rotated by the arm 32 about its ends 33. The ends 33 are disposed toward the feed side of the machine from the axis 12 of the main cylinder on a line connecting them that is inclined from the vertical approximately twentyfive degrees, with the enlarged portion of the shaft 3l' on the side of the ends 33 away from the feed side.

The feed mechanism is indicated by the numeral 3.5. The inking and dampening units are located on top of the cylinder and a curvilinear deflector located upon the delivery side is shown at 35 to catch the printed sheets and deliver them to the delivery table 31 right side up.

GENERAL OPERATION The press is constructed so that the main cylinder is driven in normal operation between 4,000 and 6,000 revolutions per hour. As it rotates the damp form roller 40 and the ink form roller 4| engage the plate on the segment 2| and are raised by the cam 42 from contact when the platen segment 22 passes below them.

With each rotation of the main cylinder the cam 23 engages the follower segment 44 mounted on the blanket cylinder 30. The cam 23 forces the blanket cylinder downwardly by displacing the eccentric shaft 3! about the shaft 33 and moving the arm 32 counter-clockwise from the stop 45. The arm 32 moves against the tension of the spring 46 whose tension can be varied by means of a catch and spaced openings assembly 43.

Just before the cam 23 relinquishes contact with the follower segment 44 the feeding mechanism 35 moves a sheet into the clearance that is established by the cam 23 between the cylinders. The speed with which the sheet is moved is an accelerating one which reaches the peripheral speed of the main cylinder just as the two cylinders are moved towards each other again by the spring acting upon the arm 32. At this time the blanket 34 prints the sheet, and the leading edge of the sheet strikes the deflector 36' and slides out upon the delivery table 37 at the end of the operation.

During the time the sheet is between the cylinders the arm 32 does not contact the stop 45. The spring 45 establishes the printing pressure independently of the stop 45 since the sheet of paper itself separates the cylinders a distance enough to prevent the full return of the arm 32 against the stop 45 when the cam 23 releases the cylinder 33.

However, when the paper is expelled from between the cylinders that clearance is taken up by the spring 45 drawing the arm 32 against the stop 45 which then comes into operation to determine the degree of pressure contact that is to be exerted between the plate and the blanket.

In feedin the sheets to the bite between the cylinders, a separating roller 41 is intermittently driven to feed the sheet 50' from the feeding tray 5| to the feeding table 52 under a feeler lever 53 resting upon the table 52. Each sheet 50 is driven by the separator 41 a distance greater than necessary for the leading edge thereto to reach the stops 54 and in this way provides a slight buckle 49 in the sheet as seen in Fig. 6.

After the sheet reaches the stops 54 the pressure roller 55 is lowered against the feed roller 55 whereupon the separator roller 41', the pressure roller 55-, and the feed roller 56 are positively driven at an accelerating speed which is only stopped after the sheet has been engaged and subjected to the bite and pull-out action developed by the cylinders.

Whenever a sheet is skipped, the feeler 53 is no longer supported by the sheet above the slot 51 and therefore the feeler drops therethrough into contact with the lug 60 upon the rocker arm 6| when the arm 62 which carries the feeler 53 is actuated by the cam surface 63. The movement of feeler 53 rotates the rocker arm BI until the free end 64 is moved from against its stop 65 to a position in the path of the lug 66 controlling the operation of the arm 32. The action of the feeler 53 is timed to take place when the cam 23 is in a position forcing separation of the cylinders, at which time end 64 is free to move into the path of the lug 66. Then when the cam 23 leaves the follower segment 44, the pressure contact which is normally resumed between the cylinders is prevented until the cam 23 again causes movement of the shaft 3| on the next revolution. By that time the feeler 53 has been returned ready to respond again to hold the rocker lever 64 down once more if a sheet is still not in feed position on the feed table.

Having thus described enough of the details of the general structural characteristics of the invention to understand the general organization and operation, reference may be had to the drawings in greater detail for a more complete description of the structural characteristics preferably employed in the printing press disclosed to accomplish the operation just outlined and the objects of the invention generally.

PRINTING COUPLE The construction of the main cylinder 20 and the blanket cylinder 30 as well as the damp form roller 43 is illustrated in Fig. 3, as viewed from the feed station. The right hand frame member It! is located upon the right hand side of the drawing and the left hand frame member II upon the left hand side of the drawing.

a. Main cylinder The main cylinder 20 is supported upon the shaft 72 which in turn has reduced end portions l3 journalled in bearing rings M that are mounted in cylindrically machined bosses I5 integral with the frame members It and II. Shoulders I6, provided by the reduction of the end portion I3, rotate against the inner faces of the bearing rings i i and confine axial movement of the shaft 2 to close limits, the bearings and shoulders being suitably lubricated by means not shown to prevent wear.

The cylinder 20, as constructed, comprises right and left hand disks TI and I8, respectively, which have annular flanges 85 that lit upon the shaft 72 to which they are secured in rigid relationship. The flanges 86 are of sufficient strength and length to support the radial portions BI and 82 against all working stresses encountered in the operation of the press.

Upon their outer faces the disks TI and I8 are provided with graduated cylindrical shoulders to receive in supported relationship various gears and cams to be hereinafter described in greater detail, it being sufiicient at the present time to identify the cams with regard to their respective locations upon the several shoulders.

At the right end of the cylinder 20, upon the disk 'Il, cams 83 and 84 are mounted with a spacing washer 85 between them. The outer cam 83 operates the separator roller 41 and the inner cam 84 operates the ductor rollers which will be identified later.

At the left end of the cylinder, the disk I8 carries three cams; cam 81 which operates the lower feed roller 56, cam which actuates the upper feed roller 55 and cam SI which actuates the ratchets upon the fountain rollers identified later. The spacer 92 is disposed between the cams 90 and SI to hold them in correct position and both cam assemblies are secured to their respective disks by cap screws engaging them in circular slots (not shown).

The rims of the radial portions 81 and 82 are machined cylindrically as at I03 to support thereon the plate segment 2I and the platen segment 22. These segments comprise semicylindrical shells structurally rigidified iby radial ribs IM upon the inside thereof and machined to a cylindrical contour upon their outer surfaces as at I05 and I66, respectively. The cylindrical contour I65 is of a radius slightly less than the radius of the cylindrical contour I06 of the platen segment by an amount equal substantially to the thickness of the plate Ifil. The purpose of this construction is to have the cylindrical contour of the cylinder of substantially the same diameter throughout when the plate IE1 is mounted upon the plate segment 2i.

The platen segment is rigidly secured to the radial portion BI by countersunk radial bolts IID (seen in dotted lines in Fig. 2) which are threaded into annular supporting flanges III that form a part of the rim of the radial portions BI and 82. On the other hand, the plate segment is apertured and countersunk to receive bolt and nut assemblies II2 which extend through the annular flanges I I I with portions cut away from the radial portions 8| and 82, as at H4, to provide access to the nut and bolt assemblies I I2.

In the preferred embodiment, two pairs of peripherally spaced bolts are employed to hold the platen segment in place, While two transversely spaced nut and bolt assemblies H2 are employed to hold the plate segment adjustably in place. The peripheral adjustment of the plate segment is accommodated by radial slots I I5, as shown in Fig. 2, permitting the bolt and plate segment to slide circumferentially on the rims I03 when the nut and bolt assemblies are loosened.

In this way a simple construction is employed to expedite locating the plate segment relative to the platen and the blanket cylinder 30 for registering and adjustment purposes.

As will be hereinafter described, the cylindrical edges of the segments 2I and 22 are machined as at IIS and III, respectively, to provide paths cooperating with wheels I20 mounted upon the form rollers 40 and II. The paths H6 and II! form arcs of circles and have different radii. Along the end edges of the platen segment 22, the whole segment is cut away or relieved at both end in identical manner to provide inclined surfaces engaging the Wheels I20, the inclined surface at the leading end comprising the cam A2 lifting the wheels.

The radial dimension of the respective paths is such that the wheels I20 will run in the paths I I1 and lift the form rollers G9 and M from possible contact with the platen when the platen segment 2I is disposed next to the form rollers. The relieved paths I I6 permit the form rollers to contact the plate I01.

A shown in Fig. 2 the plate segment 2| is provided with clamping elements at the leading and trailing edges. The leading edge of the plate segment is indicated at I22. At this edge the seg- 7. ment is rounded slightly as at I23 to provide a flat radial surface I24 against which asemi'cylindrical clamp fixture IE is rigidly fastened. Shafts I26 are eccentrically mounted in the ends of the fixture, and L-shaped clamping elements I 2'! are mounted upon the shaft so as to move in clockwise direction, as viewed in Fig. 2, to clamp and release the leading edge I39 of the plate I91 in a relationship which is tightened by the pull of the plate upon the clamping elements, the spring I3 I assisting the clamping elements in establishing this clamping relationship.

At the trailing edge 24 the plate segment is likewise rounded slightly but in this instance the clamping cylinder I35 is eccentrically mounted upon the' rocking arm I34 along with the L- shaped clamping member I33 which supports the assembly upon the plate segment. The lever I3! is employed to rotate the eccentrically mounted cylinder I35 relative to the L-shaped clamping member I33 in a counter-clockwise direction to release or receive the trailing edge of the plate. In pressing the arm I3? inwardly to do this, the arm is also pressed clockwise with regard to the plate segment to bring the sleeve closer to the rounded edge, at which position the trailing edge of the plate may be inserted between the clamping faces. Thereafter the arm IS-l' is released and a spring, not shown, actuating the rocking arm I34 draws the plate taut and automatically removes therefrom any slack developed in the plate under running conditions.

The cam segment 23 heretofore described, is mounted upon the disk 82 where the latter is cut away as at I40 (Figs. 6 and 9). In. view of the fact that the cam 23 is longer circumferentiall-y than the space between the segments 2| and 22, the segments El and 22 are cut away toreceive cam 23 axially within their borders free of wheels I20 where it will engage the cam segment 44-. Two segments 23' are provided so that one may be mounted at one end of the main cylinder and the other at the other end.

b. Blanket cylinder The blanket cylinder is made of a single casting whose outer surface isground to a cylindrical surface. Th casting includes annular flanges I46, which rotatably support the cylinder upon the shaft 3|, and is provided with a gap I-4-1 (Fig. 2) wherein the mountings for the blanket are provided. This mounting means comprises headed pegs I50 upon the relieved leading edge I'5I of the cylinder which engage keyhole. slots in the leading edge of the blanket. The trailing edge is slotted in th same way as the leading edge but the headed pegs I52 there are supported upon a movable member E53. which is subjected to the control of the hex headed bolt. I54 employed to place the proper tension upon the blanket.

Spanning the gap, as more particularly shown in Figs. 6 and 9, the follower segments 44 for the earns 23 are mounted in. recesses I56: upon the ends of the blanket cylinder. The outer contour of these follower segments extends slightly beyond the cylindrical surface of the cylinder 39 yet not quite to the outer surface of theblanket. In. this way the segments 44 do not project far enough to engage any portion of the main. cylinder other than the cam 23. Thisis tobe noted since the blanket cylinder. rotates. twice in the illustrated: form while the: main cylinder is being rotated once;

0. Printing pressure regulation The blanket cylinder 3! is rotatably mounted uponan eccentric shaft 3I which permits contact pressure regulation between the cylinder 30 and the: main cylinder 20, as already described generally'. In providing this mounting, the shaft 3| rotatably carries the cylinder 30 on the outside surface thereof and in turn is rotatably mounted upon eccentric reduced end portions 33 provided concentric with each other at both ends of the shaft. On the left hand side, the shaft is journalledin and extends beyond the frame II, as at I:4 I, where it receives the manual control handle I42. At its other end, the end portions 33 are rotatably journalled' in a bearing sleeve I43 which in turn is received in the frame member HI and carries upon its outer side a second sleeve hearing supporting a free running gear I45 meshed with a gear I48 upon. the main cylinder 20.

Rotation of the blanket cylinder is accomplished from the main cylinder through a universal joint 51 known in the art as an Oldham coupling which interconnects the end of the cylinder 30 and the gear I45.

Rotation of the handle I42 eccentrically r0- tates the shaft 3| about the ends 33, the shaft being. so disposed that its greatest diameter yields in a direction of the pressure induced upon. it when the main cylinder rotates and the cam 23 engages the follower 44.

At no time is the separation of. the cylinders great, the distance being. merely enough to clear possible contacts and. provide a space into which the sheet 50 may be inserted and gripped by the cylinders when they return to contact after the cam: 23 and the follower 44 separate. Even at the extra high speeds under which the cylinders have been run in tests there is little if any vibration. The throw of the cam 23' moves the blanket cylinder such a smalldistance that it is hardly detectable by the eye. In fact, as shown in Fig. 6, it will be' noted that even the movement of the arm 32, which is magnified greatly because of the leverage induced by displacement of the eccentric shaft,v is not very great. This magnification of the movement of the arm 32, how'- ever, is purposely done so that the adjustment of the stop 45 can be brought to a fine point without undue care being. necessary.

With regard to the adjustment of the stop 45, it will be remembered that the cylindrical surface presented by the main cylinder, while the plate is in position, is of substantially uniform diameter throughout.

The stop 45 is adjusted so that it, in cooperation with the arm 32, determines precisely the distance between the axes of the main cylinder and the blanket- This distance determines the pressure which will exist between the plate upon the main cylinder 20 and the blanket upon the blanket cylinder 30. This pressure is uniform and positive within limits that do not cause the arm 32 to leave the contact 45 against the action of the spring 46..

However. when the. blanket isready to transfer the ink to the sheet 50, the printing pressure should be and. is greater than that of the transfer pressure due to the fact that the diameter of the platen segment is the same as that of the plate segment and: the thickness of the sheet 50, when in position between the blanket and the platen segment, causes: the printing pressure to be subjected tothe tension of the spring 46 by wedging the cylinders further apart and forcing the arm 32 to leave the contact 45. The tension can be varied by adjusting the tensioning device 43. This is the relationship of the printing and transfer pressures as controlled by the eccentric shaft, the stop 45 and the spring 46.

It has already been pointed out that little if any vibration exists between the cylinders, even when they are driven at high speeds. In addition to this, the arm 32 does not move from its position, as shown in Fig. 6, into. direct contact with the stop 45 to jar against the stop or cause a slapping action, since, when the cylinders are relieved of contact between the cam 23 and the follower 44 they come together upon the sheet 50 whose thickness supports the arm 32 away from the stop 45. Thus when the cam 23 and the follower 44 separate, the arm 32 comes quickly to a point spaced from the stop 45 and only reaches the stop 45 after the sheet 56 has been delivered. This action of the arm 32 prevents noise and wear upon the stop 45 and the arm 32.

This separating action of the cylinders upon each revolution by the arm 32, the cam 23 and the follower 44 has a further advantage. The parts involved in making adjustments are not permitted to seat themselves in strained positions which would render delicate adjustments impossible as is the case in conventional constructions, and. in addition to advantages derived in providing a perfectly registered bite for the sheet 56, the pressure adjusting separator movement of the blanket cylinder makes it possible to have an improved control for keeping the cylinders separated in event a sheet is skipped by the feeder.

From the description thus far it will be readily apparent that the elements employed in the printing couple, their structural characteristics, assembly and operation are quite simple. The number of adjustments are minimized and those that are provided can be made easily by persons who happen to be unskilled in the printing field. The means for positioning the plate and blanket are quite simple and once the plate is located by the nut and bolt assemblies II2 only one adjustment need be attended to thereafter, namely, the adjustment of the stop 45.

FEEDER It has been mentioned that a line connecting the axes of the cylinders is inclined to the vertical approximately twenty-five degrees. This position places the plane of tangency between the cylinders in a position inclined to the horizontal, slopping downwardly away from the feed position. The degree of inclination is preferably within a range having a mean of 25 or 30 and the magazine table 5I carrying the sheets 56 is disposed in a plane approximately parallel, though slightly below said plane of tangency. Thus the sheets of paper 50 are permitted to gravitate to the lower edge of the magazine 5| without manual attention, yet do not bear against the separator roller 41 heavy enough to buckle under their own weight,

The magazine 5| is mounted detachably upon the frame members and II on the feed side of the cylinders 20 and 30 with the lower edge very close to the cylinders. and almost substantially within the combined contour of the two cylinders the improved and compact feeding mechanism is mounted. As has already been mentioned, the main elements comprise an intermittently driven separator roller 41, a retard roller 48 and two positively driven At the lower edge- 10 sheet moving rollers 55 and 56, the last of which has associated with it a sheet registering device generally designated I60 and more particularly shown in Fig. 12.

a. Registry The sheet registering device I60 operates in synchronism with the cylinders 26 and 30 and functions by having stop fingers 54, associated with the lower feed roller 56, moved to an upright position for a given portion of the cycle of the presss operation to receive and register a sheet delivered to them from the separator roller 41.

The separator roller 41 is intermittently driven by the pitman I62 shown in Figs. 4 and 10 which in turn is propelled by the rock lever I63 pivotally mounted at I64 and driven by a follower I65 engaging the cam 83. An overrunning clutch I66 is interposed in the drive of the separator roller so that the sheet 50 when pulled off the stack by the bite of the cylinders will be fed without hindrance from the separator roller even though the intermittent drive through the pitman has ceased. This intermittent drive includes the shaft I61 which is rotatably mounted in the side frames of the presses and an adjustable bolt and slot assembly I68 to vary the throw of the pitman I62.

The retard roller 48 is mounted on a shaft I10 provided with eccentric trunnion bearings (not shown) journalled in the side frames of the press. The bearings are so located with respect to the shaft I61 carrying the separator roller that the retard roller 48 is in substantially tangential contact with the separator roller. The aXis of the trunnions is so positioned that bodily movement of the retard roller 48 in a direction imposed by the sheet advancing causes the retard roller to move forward slightly and away from the separator roller 41.

However, the shaft I10 is constantly urged in the opposite direction by suitable means and is limited by a suitable stop (both of which are not shown) which gages the distance between the retard roller 48 and the separator roller 41 to permit only one sheet to pass therebetween when the pitman I62 actuates the separator roller 41.

The sheet 50 as drawn from the stack by the separating roller is propelled forwardly upon the feed guide plate 52 a distance greater than necessary for it to reach the register stops 54 after which the sheet is brought to a stop with enough expanse of sheet between the separator roller 41 and stop 54 to provide the substantial buckle 49 in the sheet. This assures registry at all times. In moving over the feed guide plate 52, the sheet passes under the feeler 53 and prevents the feeler from dropping through the slot 51. The feeler 53 is thereby kept from contact with the lug 60 upon the arm 6| which would cause the latch 64 to engage the lug 66 upon the eccentric 3| and prevent return of the arm 32 after the cam 23 and follower 44 relinquish contact. The eccentric shaft 3I is thereby left free to move the blanket cylinder into contact with the main cylinder when the sheet 50 is therebetween.

After the buckle 49 in the sheet 50 is established, and in timed relationship with the rotation of the main cylinder, the upper feed roller 55 is lowered by the cam which actuates the follower arm Ill, and thereby the roller support bail I12 through the pivot pins I19 (Fig.

14). When lowered, the upper roller 55 contacts the lower roller 56, with the front edge of the sheet between them. After this contact has been established the lower roller '56 is automatically rotated to accelerate and deliver the sheet into the space between the cylinders at a speed whose ultimate velocity is identical with the surface velocity of the main cylinder 20. This drive is accomplished from the cam 81 and a gear segment 9.4 pivoted at 9'5 with the follower between at 96.

As the lower roller 56 -is driven, the separator roller 41 may also be driven further forward simultaneously to maintain the buckle 49 in the sheet between the feeder rollers and the separator roller so as to prevent any undue strain being placed upon the sheet on the feed rollers.

Once the cylinders 28 and 38 come together upon the sheet 58 (if not before) the drive of the separator roller is stopped. lhe over-running clutch comes into operation and the upper roller '55 is raised to permit the bite between the cylinders '20 and 30 to complete the operation of the withdrawingof the sheet from the stack.

Not only does the maintenance of the buckle in the sheet prevent undue strain, it also prevents feed slippage arising between the feed rollers 55 and 56. Their operation is comparatively free of any substantial draw and it is not the intention of the invention that these rollers be used to pull the sheet from the stack. The main portion of this operation is done by the cylinders themselves as assisted by the .separator rollers during the time the latter operate. The feeder roller-s are merely burdened with accelerating the free edge of the sheet to .a registering position between the cylinders. In this way accurate feeding of the sheet in perfect registry is assured and the longevity and efiectivenss of the feed rollers is greatly enhanced since they are in operation during only a small portion of the feed movement of the sheet.

MOVEMENT or REGISTRY STOPS The action of the end registering fingers will now be described. The stops 54 are carried upon segments mounted upon the shaft 1 T3 which supports the lower roller 56 (Fig. 12) These rollers are driven, as already described, through a gear H4 in mesh with a gear segment 94 that in turn is actuated'by the cam 81 mounted upon the main cylinder 20. The setting of the driving train is such that when the sheet 50 contacts stops :54 they are normally vertical, being held in this position by a return spring I16 which through the gear train maintains the follower 96 firmly against the cam 81.

Immediately after the separator roller 41 feeds a sheet against the stops 54 with the buckling action, and after the pressure roller 55 is lowered, as already described, to grip the leading edge of the sheet firmly, the cam 81 operates the gear segment 94 to rotate the feed roller 55, and, at the same time, to rotate the stops 54 away from the leading edge of the sheet as it is advanced by the roller 55. The feeding of the sheet follows as has been already described. When released by the cam 81, the cycle of the stops is completed by the return of the feed roller 56 and the stops 54 to their initial position under the influence of the return spring I1 6, which incidentally eliminates all slack from the drive of the feed roller 56 so that the feeding of the next sheet and all successive sheets is absolutely uniform.

INKING AND DAMPENING The inking and dampening rollers are located .above the main cylinder. The ink fountain I is disposed between the frame members upon the feed side of the press and the water fountain I8I is disposed betwen the frame members upon the opposite side of the press. Between these two fountains the rollers are all mounted with their axes lying preferably substantially in one plane.

The form rollers 40 and 4|, already described, are proximate each other and supported for vertical movement intermediate the ends of the rocker arms I 82 which at their adjacent ends carry cam followers I83 that ride upon a common cam I88. The followers I83 are adjustable by means of eccentric bolts I88 to regulate the pressure between the form rollers and the plate.

The pivotal axes of the arms I82 are the shafts I85 supporting the respective distributing rollers, namely, the water distributing roller I86 and the ink distributing roller I 87. In this manner of supporting the arms I82 the form rollers are never out of contact with their respective distributing rollers.

As best shown in Fig. 1, the followers I83 engage the cam I84 at points spaced about 90 where the reduced dwell I9I is of suflicient length to receive them both at the same time. The larger dwell 199 of the cam I84 though about 180, may be less than 180 provided the inclines themselves never exceed the angularity between the follower-s.

The cams I 84, there being one on each side of the press, are mounted on the shaft I92 which carries on the end thereof a handle I93 where the shaft extends beyond the side frame II. Both form rollers are lowered when the handle extends straight down. When the handle is turned to a horizontal position extending toward the feed side, the ink form roller is raised. When the handle is turned away from the feed side of the press the dampening form roller is raised, and when the handle I93 is turned to point straight up both form rollers are raised. This construction provides a very effective form roller throwout mechanism which is simple in construction and easily understood. An unskilled operator would learn quickly to detect whether the form rollers individually or together are in their off or on" position by the direction of the handle. Suitable detents (not shown) are provided for locating the handle in the four positions described.

As part of the ink and water distributing system I provide an improved mechanism for actuating the ductor rollers, roller I94 being the water ductor and roller I95 being the ink ductor. These mechanisms comprise identical parts mounted in reverse for the water and ink ductor rollers respectively. As shown in Fig. 2 each mechanism comprises a shaft I96 journalled in the side frames and provided with upwardly extending spaced yokes I9! and downwardly and inwardly extending follower arms 280 that engage, in common, the cam 84 and are adjustable arcuately about the bolt I99. The contour of the cam 84 is shown in Fig. 2 in proper relation to the segments 2I and 22 so as to move the ductor rollers in timed relationship with the rotation of the main cylinder 29.

The ductor rollers are rotatably mounted upon the shafts 292 journalled in boxes 283 that are slidably mounted between the yoke arms 204 of the yoke member I91. Thus the ductor rollers are free to rotate in relation to any roller with which either comes in contact. Springs 205 are employed to retain the followers against the cam 84.

INK Duc'roa THROW-OUT necting the free end 2 I3 of the arm with an up-v wardly extending arm 2M secured to the yoke I91. In this particular construction the yoke I9! is permitted enough relative movement counter-clockwise about the shaft I95 when the arm 2|!) and spring 2I2 are disposed in their alternate positions, as indicated by the numeral 2I5 in Fig. 16.

INK FOUNTAIN The ink fountain I80 comprises an ink roller 2I6 rotatably mounted in the mouth of a horizontally opening casing 2!? which is fitted with a flexible steel blade 22%] regulated by means of fine threaded thumb screws 22! set close to gether with short rollers 222 placed end to end between the blade and the adjusting screws 22L The rollers provide an improved fountain construction wherein pressure upon the blade is never localized at a point but is spread uniformly for each screw 22! throughout the length of the roller which allows the flow of ink to be regulated to a nicety at any section and throughout the full length of the blade. In this way a very effective and simple control of the ink feed clearance between the blade and the roller is provided which supplies a substantially uniform film of ink upon the surface of the ink rollers 2 I8 throughout their length.

WATER FOUNTAIN The water fountain includes a water tray 223 with the water fountain roller 224 running partly submerged therein, the tray being mounted upon side frames by a bracket 225 and the water roller being mounted for rotation upon a shaft 225 journalled in bosses preferably integral with the side frames.

FOUNTAIN ROLLER ACTUATION The ink roller and the water roller are operated by an improved pawl and ratchet arrangement of wide adjustment that is driven in timed relationship with the rotation of the main cylinder 20. Each of the pawl and ratchet arrangements for the ink and water rollers are designed from parts that are simple in their construction. These parts comprise a rocker arm 236 which is pivotally mounted intermediate its ends on a spur bearing 23L At its end 232 the arm has a follower which engages the cam 9i whose contour and location regarding the main cylinder is as shown. The upper end 234 of the rocker arm 23!] is connected with the lower end 235 of a second rocker arm 236 by means of a thrust link 231. The second rocker arm 236 is pivotally mounted intermediate its ends to rotate about the axis of the roller H3, and carries at its upper end a pawl 240 engaging a ratchet 24! rigidly secured to the shaft of the roller 2H5. A

14 spanning link 238, running to the ratchet 239 upon the shaft 225 of the water roller 224, is driven from the link 231.

The ratchets 239 and MI are disposed identically 0n the shafts of the fountain rollers 2IB and 224. The rollers 2") and 224 rotate in the same direction. The linkage is such that the ink ratchet 24I operates on the thrust of the cam 9! so that the heavy pull of the ink roller is borne on the cam thrust stroke, and the water ratchet 239, which has a much lighter load, is operated by the spring 233 upon the return movement of the follower, the spring 233 thus serving a dual purpose as a cam follower return and as fountain roller actuator. The direction of turning the ratchets is, of course, that in which the ink roller 2I6 rotates in correct relationship to the blade 220. In this way not only are surplus parts eliminated, but the remaining parts are standardized to be identical for inventory purposes and are made very simply.

ROLLER MOUNTINGS Referring to Fig. 3, the arms I82, supporting the form rollers 48 and 4!, are shown as apertured to receive eccentric bushings 243 on the arms I82, which may be adjusted by loosening the clamp nuts 242 upon the threaded reduced end of the bushing 243, where it extends through and beyond the arm I82. These bushings receive a cylindrical shaft 254 therethrough, which, intermediate the inner ends of the bushing 243, rotatably carries bearing sleeves 245 which support the wheels I2!) and the cylindrical iron stock 245 upon which the rubber covering 241 is cast.

With this construction the roller can readily be removed from the press without disturbing its adjustment by withdrawing the shaft longitudinally through the side frame Iii, a knurled end portion 24? of the shaft being provided to assist in this and the side frame Ii! being cut away, as at 248, in the form of a vertical slot which accommodates the end of the shaft 244 as the roller moves up and down during its working cycle.

If any axis of the rollers or cylinders is not exactly parallel with the axes of the others, both ends of that roller. can be adjusted independently by the means provided until all axes are perfectly parallel. In this way a simple and easily adjusted mounting for each bearing is provided, with all parts standardized to reduce-inventory overhead for both the manufacturer and the dealer, like numbers referring to like parts in the several Views.

INK DISTRIBUTION Referring now to the timing of the ductor rollers and the feeders, and to the kinematics of the inking and dampening assemblies, it is to be noted that perfect distribution of dampening fluid and ink upon the plate is accomplished by two assemblies of only three rollers each, one of which in each group is the respective ductor. The relative diameters of the three rollers in both the dampening assembly and the inking assembly is significant. In the preferred embodiment. as shown in the accompanying drawings, the ink distributing roller I81 and the water distributing roller I86 of the respective inking and dampening assemblies are larger than the other rollers in their respective assemblies.

The following explanation will be restricted for the sake of simplicity to the inking assembly 15 although what is said applies to the dampening assembly also.

The size of the ink distributor roller I8! is such that it revolves about 2 /2 times in the period of time that the form roller 4! is not in contact with the plate I01, and in the particular embodiment this amounts to about four revolutions while the main cylinder 20 is making one complete revolution.

The form roller 4! is of a size such that it revolves about three times during the time that the distributing roller revolves the above mentioned 2 times. The ductor roller I95 is constructed of a diameter so as to revolve approximately 4% times while the distributor roller is revolving 2 times. With these ratios disclosed by way of giving a suitable example of the relative dimensions, it will be seen that any two contacting points between the rollers do not come together again within the period of time existing between the breaking and making of contact between the form roller and the main cylinder. With the ratios provided in the preferred form, with each revolution of the distributor roller, the form roller turns 1 /5 times and the ductor roller turns 1 /5 times, and, the ductor roller revolves 1 times for each revolution of the form roller. With these ratios it is possible to introduce an even layer of fresh ink upon the ductor roller over a substantial segment of its outer surface when it is in contact with the inking roller without that segment of fresh ink overlapping itself within the 2 /2 revolutions of the distributor roller. Thus in the interval between the time the form roller breaks contact with the plate I0! and again makes contact with the plate there is adequate time for substantial distribution of ink to take place. However, in the construction of the present invention, the size of the rollers and the timing of the ductor roller provides more time than this within which ink may be distributed for transfer to the plate.

I employ a means for inking the distributor roller at a time synchronized with the rotation of the cylinder when the path the fresh ink has to follow before it would otherwise come into contact with the plate surface for the first time is appreciably longer than the path yet to be followed by the circumference of the cylinder remaining to be contacted by the form roller at the time the ink is transferred to the distributing roller.

In the relationship of the relative diameters, as shown, it will be seen that there is enough time provided for another revolution of the distributor roller from the time the ink is transferred thereto to the time that the form roller picks up the fresh ink and contacts the plate with it. This means that when the main cylinder is rotated, as shown in Fig. 2, to a point where the form roller contacts the plate at 250, the ductor roller may transfer fresh ink to the distributor roller without any of that fresh ink reaching the plate until the next contact between the form roller and the plate, namely, until the leading edge I22 of the plate segment brings the plate again into contact with the form roller. The illustrated arrangement provides an additional margin of safety since the ductor roller has to rotate more than A; of a revolution before fresh ink thereon is in a position to come into contact with the distributing roller after being moved by the cam arm 200 into contact with the distributing roller.

The discussion so far has been related to the distribution of fresh ink. A great deal of the distributing action induced between the ink assembly rollers continues after the leading edge I22 of the plate segment is again in contact with the form roller since the form roller 4| provides approximately /3 of a revolution after contact with the plate before the ink distributing roller I 87 has to replace the ink taken from the form roller by the plate. This in point of time would be approximately where the form roller would reach contact with the plate at 25L This provides approximately 330 of revolution of the main cylinder within which the inking assembly is devoted entirely to ink distribution. It is only for approximately the remaining 30 of revolution of the main cylinder that the inking assembly is burdened with supplying ink to the plate by drawing ink twice from the same part of distributing roller IS! without intermediate replenishment, this being the are between point 251 and the point 250.

Thus it will be seen that the structural characteristics disclosed and described and the operation thereof provide an improved inking system for plate cylinders. It remains only to point out in this connection, that with the more accurate and efiicient blade control provided, it is possible to supply films of ink to the ink rollers which are thinned down a great deal without endangering the uniformity of distribution. With the ink thinned down, it is possible to rotate the ink roller through a wider arc by a long throw upon the pawl 240. The ductor roller when it contacts with the distributor roller thus has the ink it received from the ink roller already distributed upon its surface more than heretofore provided upon conventional ductor rollers so that when the replenishing ink is picked up by the distributor roller, it is already distributed well over the face thereof, the relative size of the rollers in the ink assembly, as already pointed out, being such that a wide sector of fresh ink upon the ductor roller will not overlap itself within two or three revolutions of the distributor roller.

POWER TRANSMISSION The transmission of power throughout the press is best shown in Fig. 4. The prime mover for the press is a motor 250 that is connected to a shaft 26l by a pulley and belt assembly 262. The shaft 26l is suitably journalled to the side frames and carries a pinion gear 263 which meshes with the ring gear I48 secured to the disk 11. The separator roller 41 is powered through the pitman I62 by means of the cam 83 also mounted upon the disk 11 and the distributing rollers I86 and I8! powered through countershaft gearing 265 for positive rotation. The blanket cylinder 30 is shown with ring gear I45 in mesh with the ring gear I48 for synchronous and positive rotation therewith as already described.

CAM TnvnNc It would now appear to be in point to discuss the timing of the cams, having alluded to certain characteristics thereof and having described all the elements and assemblies involved. The following figures and dimensions are used by Way of example and are not to be interpreted as limitations.

About 90 before the cam 23 upon the cylinder 20 engages the cam 44 upon the blanket cylinder 30, namely, at about the time the point 250 upon the cylinder 20 engages the cylinder 30, the cams 83, 81 and 90 are located in their zero positions as shown in Figs. 10, 11 and 13. Within the 90 turn of the cylinder 20 that follows, the cam 83 uses the first 40 to actuate the separator roller 41 and thereby move the front edge of the sheet 50 against the stops 54 with sufficient slack in the sheet to provide the buckle 49. Within the next 9 the upper feed roller 55 is lowered to grip the leading edge of the sheet.

The respective parts are maintained in their respective positions thereafter until the cylinder has rotated 65 from its original position whereupon the follower I65 leaves the dwell 300 on the cam 83 and is driven farther out by the incline 39I simultaneously with the drive of the follower 96 by the incline 302 upon the cam 81. This simultaneous drive starts the accelerated, registered feed movement of the sheet towards the bite with the contour of the inclines MI and 302 cooperatively assuring the retention of the buckle 49 in the sheet.

Shortly after the feed movement has begun, the cams 23 and 44 engage and the cylinders 20 and 30 are separated. By that time the cam 63, which is carried by the arm 94, has moved to a position where the incline 303 actuates the follower 304 upon the arm 62 to operate the feeler mechanism (Fig.

With the sheet 50 holding up the feeler 53, the arm 32, under the tension of the spring 45, is permitted to establish the printing pressure between the cylinders when the cams 23 and 44 relinquish contact.

By the time the cylinders 20 and 30 come together again, the sheet is moved approximately 4 of an inch beyond the center line where and at the time the bite takes place.

Immediately after the bite is established, the upper feed roller 55 is raised and the follower 96 enters upon the decline 304a of the cam 81 to return the stops 54 and lower the feed roller 56 gradually to their initial position, the pitman I62 being returned at the same time.

In the meantime the plate has been in contact with the form rollers 40 and M. Within the 132 of cylinder rotation before the point 250 on the cylinder 20 reaches the ink form roller 4|, the ink roller ratchet 24I has been actuated for the first 95 thereof by the cam incline 305 (Fig. 1) during which the ink ductor follower 200 (Fig. 2) has been free of contact with the dwell 306 upon the cam 84.

During the remaining 37 of the 132 the ductor roller I95 is moved from the ink roller 2I6 to the distributor roller I81 by the incline 301 upon the cam 84, by which time the water ductor arm 290 reaches the dwell 306.

Also within said 37 the ratchet follower 232 has come to the end of the high dwell 3I0 upon the cam 9| and for the following 95 of revolution, the ratchet arm 238 is moved by the spring 233 to rotate the water fountain roller 224 in synchronism with the time the ductor roller I94 is against the water fountain roller 223. Thus within this last 95 of revolution, the damp is picked up by the ductor I94 and thereafter the incline 301 of 35 upon the cam 84 moves the water ductor roller I94 back against the water distributor roller I86.

The high dwell 3H upon the cam 83 keeps the ductor rollers in contact with their respective distributor rollers for the remaining 138 turn of the cylinder 29 throughout which they will function as distributor riding rollers.

TYPE AND Dnmc'r PRINTING The invention, as shown in Fig. 15, is adapted for direct printing. Although it is preferable to employ the blanket covered cylinder 30 as a platen, a hard surface cylinder (not shown) could be substituted for the blanket covered cylinder 30, if desired, to cooperate with the type supporting segment 210 mounted in place of the platen 22. A counter-weight segment 21I is, in this instance, substitutedfor the plate segment 2i. In the event the type segment 210 is one which is long enough to cover a larger portion or practicall all of the circumference of the cylinder 29, the hard surfaced platen cylinder (not shown) will be one with a continuous outer surface, In this construction, the dampening assembly can either be removed completely from the press, as shown, or be held out of engagement by rotating the handle I93 away from the feed side of the press, an expedient not shown in the drawing.

In the adaptation shown, the form roller M contacts the type supported in the type channels 212 of the type segment 219 and in this instance,

a stationary stripper 213 is employed to break contact between the paper fed between the cylinder and the blanket roller 30 which now serves as a platen instead of an impression transferring medium. The delivery table is indicated at 215 below the stripper 213. All of the functionings of the modification shown in Fig. 15 correspond with the description of parts contained herein covering the preferred form of the invention, except that ink form roller 4! is held off of segment 21I, as clearly seen in Fig. 15.

In this Way, the press disclosed and described herein is readily adaptable to print directly or indirectly upon the sheets of paper 50 fed to it by the feeding mechanism 35. This is one of the features covered by the patent resulting from the application of which the present application is a division.

SHEET DELIVERY The delivery mechanism for both constructions will be described and compared at this time, having in mind certain objects already alluded to and other advantages and new results provided by the construction as shown. Referring to Fig. 2, the deflector 36 is a single casting comprising spaced curved ribs 214 that follow the contour of the impression cylinder 30'over a portion of its length, ending in straight portions 211 that carry the sheet 50 far enough to assure it reaching the delivery table 31. The curved ribs are joined at their ends by three integral cross sections 218 with the intermediate sections thereof terminating at both sides of the deflector in lugs 219 which receive bolts 216 that detachably support the deflector between the side frames 10 and 1!. The sheet contacting edges of the ribs are polished preferably round to facilitate sheet movement.

Referring to Figs. 1 and 2, where the printing ink is applied to the bottom of the sheet 50 by the blanket roller 30, the deflector 36 is mounted to catch the sheets 50 as they come from between the two cylinders and to right them for delivery onto the delivery table 31 with the printed side up. The stripper 213 in this instance is mounted below the blanket cylinder 30.

In the direct printing adaptation shown in Fig. 15, the main cylinder 20 places the ink on top of the paper and a delivery mechanism is 19 provided which also delivers the printed side of the sheet up. i

In th construction shown in Figs. 1 and 2, the printed sheet is seldom touched by the stripper. The arrangement of parts is such that the peripheral speed and centrifugal throw of the blanket cylinder flings the sheet free practically every time without the stripper being needed to assist. The deflector engages the back side, i. e., dry side of the sheet without ever touching the printed ink arrangement} This is of particular interest in that when the direction of the sheet is changed and the sheet is forced to follow a path not normal to the direction it would follow if it were free to move after being discharged from between the printing cylinders, a great deal of frictional contact and pressure is exerted between the handling member and the surface of the sheet where the imposed path of the sheet is curvilinear.

In the present invention, this friction is capitalized upon to prevent a sheet driven at high speed from striking the registering stops of the delivery table hard enough to nick the leading edges of the sheet, yet the sheet is delivered positively without any danger of smearing the fresh ink upon the printed surface thereof.

INK CLEAN-UP In Fig. 16, I show an improved clean-up attachment for the ink rollers. This attachment comprises a metal tray 280 adapted to slide into position upon a cross sectionally rectangular strut member 28| connecting the side frame members. The length of the cleaning attachment is approximately one-half the length of the rollers and its end members 282 extend forwardly beyond the front wall 283 a sufiicient distance to provide for slots 284 which slip over the strut 28! and assist in locating tray 288 in place. Along its upper edge the front wall 2&3 is inclined forwardly as at 285 toward the center of the distributor roller I81 as the tray 289 is located in place. The front edge 28% of the inclined portion 235 has secured thereto a flexible blade 281 made preferably of synthetic rubber, such as Duprene, which is adjustably held in place by nut and bolt assemblies 290 to contact the circumference of the distributor roller when the tray is in its resting position.

During the cleaning operation, the tray 280 is placed first on one side and manually forced lightly against the surface of the circumference of the distributor roller I81 to clean therefrom ink present there. The strut 28! and slots 284 operate as stops to preventcrowdin the metal tray against roller I 81, and asolvent, such as gasoline, is used to loosen the ink, the solvent being applied to only that half of the roller. After one end of the roller is cleaned, the tray is slid gradually along the strut 28! to clean progressively through to the other end of the rollers.

The length of the tray 280, although providing a saving in material, primarily is designed to teach inexperienced operators that only onehalf of the rollers length is to be solvenized at a time. Although in the present invention, this factor is not so important, it is important where there are many frictionally driven riders and other rollers. By solvenizin' only half the length of the roller, ink tackiness on the remainder of the rollers drives the riders'until the cleaned portion dries to providea dry friction that assists 20 in cleaning the remaining portion of the rollers. slippage betweenthe rollersisthereby avoided which would be engendered, if solvent were appliedthroughout,"the'solvent and ink solution be n quite slippery.

In this cleaning operation, the snap-over arm 2| p'is located in'the' position H5 and the ductor roller I-95 is continuously held against the distributor roller I81. 'The cleaning operation is done with the press running and the handle I93 up so that none of the gasoline reaches the plate.

In this process, the gasoline is transferred back and forth between all the rollers to loosen the ink and carry it down into the tray 280. The rollers dry right away without inking, the press being thereby prepared for the next run quickly and in a very simple manner with no saturated rags or waste to be disposed of to prevent spontaneous combustion, and no soiling of the hands or clothes.

Having thus set forth and described the advantages of the invention and the structural characteristics of a preferred embodiment thereof, it will be appreciated that the various constants and dimensions set forth are used for purposes of illustration only and can be varied if compensatory changes are made in other parts of the device. Consequently, although certain embodiments of the'present invention have been shown and described in detail herein, it will be apparent to those skilled in the art that various modifications and changes may be-made therein without departing from the spirit and substance of the invention, the scope of which is commensurate with the appended claims.

half the diameter of the upper drum and having its longitudinal axis offset, in the direction from which the sheets are fed from the vertical plane which includes the longitudinal axis of the upper drum, means for mounting either a lithographic plate or a type plate upon the upper cylinder, means whereby the lower cylinder may act either as an offset surface or a platen depending upon the type of plate used on the upper cylinder, means for delivering printed sheets from the printing couple forwardly in the event that direct printing is being done, and means for delivering sheets real-wardly toward the sheet feed, after carryin the sheet approximately half way around one of the members of the couple in the event that offset printing is being done, whereby the sheets are in both cases stacked with their printed faces up.

2. In a printing press, a printing couple including a cylinder and adapted to print optionall'yeither the'top'or bottom face of a sheet fed to'the couple, means optionally effective for stripping a sheet from the printing couple'and delivering it as it leaves the bite of the printing couple, and means alternatively effective for stripping the sheet fro'm'the" cylinder after it haspassed approximately half'aroun'd the cylinde'r'an'dto deliver it with itsoriginal under face 3. In a printing press, a'printing couple including a cylinder and adapted to print optionally either the top or bottom face of a sheet fed to the couple, means for stripping a sheet from the printing couple at a point closely adjacent to the couple when one face of the sheet is printed, and for stripping a sheet at a point approximately halfway around the cylinder when the other face of the sheet is printed thereby to deliver the sheet printed face up, and a deflector to insure passage of the sheet approximately halfway around the cylinder when said other face of the sheet is printed even though the sheet does not adhere to the cylinder to said second point of stripping,

4. In a printing press, a printing couple including a cylinder and adapted to print optionally either the top or bottom face of a sheet fed to the couple, said cylinder including a blanket for offset printing when the under face of the sheet is printed and being the lower member of the printing couple, means for stripping a sheet from the printing couple at a point closely adjacent to the couple when the top face of the sheet is printed and for stripping a sheet at a point approximately halfway around the cylinder when the bottom face of the sheet is printed by oifset printing thereby to deliver the sheet printed face up, and a deflector positioned to insure passage of the sheet approximately halfway around the cylinder when the bottom face of the sheet is printed even though the sheet does not adhere to the blanket to said second point of stripping.

5. In a printing press, a printing couple including a cylinder and adapted to print optionally either the top or bottom face of a sheet fed to the couple, said cylinder including a blanket for offset printing when the under face of the sheet is printed and being the lower member of the printing couple, means eifective when the top face of the sheet is being printed for stripping a sheet from the printing couple and delivering it as it leaves the bite of the printing couple, and means effective when the bottom face of the sheet is printed for stripping the sheet from the cylinder after it has passed approximately halfway around the cylinder and to deliver it with its printed face up.

WILLIAM WARD DAVIDSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,211,766 Brown, Jr Aug. 20, 1940 1,558,686 Lipton et al. Oct. 27, 1925 666,484 Brooks et al. Jan. 22, 1901 629,915 North Aug. 1, 1899 2,220,255 Marchev et al. Nov. 5, 1940 1,091,841 Hermann Mar. 31, 1914 2,075,950 Marchev et al. Apr. 6, 1937 2,094,628 Whitehead Oct. 5, 1937 2,140,256 Aberle Dec. 13, 1938 2,165,231 Curtis July 11, 1939 2,164,707 Ford July 4, 1939 1,968,850 Morse Aug. 7, 1934 1,837,671 Pirie Dec, 22, 1931 2,341,020 Curtis Feb. 8, 1944 

